package com.spring.boot.spring.service.impl;


import java.io.UnsupportedEncodingException;
import java.security.AlgorithmParameters;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.Security;
import java.security.spec.InvalidParameterSpecException;
import java.util.Arrays;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.StatusLine;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.springframework.stereotype.Service;

import com.alibaba.fastjson.JSON;
import com.spring.boot.spring.service.WechartUserService;
import com.sun.org.apache.xerces.internal.impl.dv.util.Base64;

import net.sf.json.JSONObject;

@Service
public class WechartUserServiceImpl implements WechartUserService {
	
	private String AppID = "wx68a30092900891bd";
	private String AppSecret = "f175c01e3127c680f05e2ca255b75a7d";
	
	private String code;
	private String iv;
	private String encryptedData;
	
	private String sessionKey;
	private String openid;

	@Override
	public UserInfo getUserInfo(String code, String iv, String encryptedData) {
		
		this.code = code;
		this.iv = iv;
		this.encryptedData = encryptedData;
		
		String entityStr = this.getSessionKey();
		
		JSONObject obj = JSONObject.fromObject(entityStr);
		
		this.sessionKey = (String) obj.get("session_key");
		this.openid = (String) obj.get("openid");
	
		this.getUserInfos(this.code, this.sessionKey, this.iv);
		
		return new UserInfo("张波", "我爱你");
	
	}
	
	public String getSessionKey () {
		
		String url = "https://api.weixin.qq.com/sns/jscode2session?appid=" + this.AppID + "&secret=" + this.AppSecret + "&js_code=" + this.code + "&grant_type=authorization_code";
		String entityStr = null;
		
		HttpGet httpGet = new HttpGet(url);
		HttpClient httpClient = new DefaultHttpClient();
		
		try {
			
			HttpResponse httpResponse = httpClient.execute(httpGet);
            HttpEntity entity = httpResponse.getEntity();
            StatusLine statusLine = httpResponse.getStatusLine();
            int statusCode = statusLine.getStatusCode();
            System.out.println("statusCode:"+statusCode);
            entityStr = EntityUtils.toString(entity);
            System.out.println("响应返回内容:"+entityStr);
		
		} catch (Exception e) {
			
			// TODO Auto-generated catch block
			e.printStackTrace();
		
		}
		
		return entityStr;
		
	}
	
	public static com.alibaba.fastjson.JSONObject getUserInfos(String encryptedData, String sessionKey, String iv){
	    
		// 被加密的数据
	    byte[] dataByte = Base64.decode(encryptedData);
	    
	    System.out.println("dataByte" + new String(dataByte));
	    
	    // 加密秘钥
	    byte[] keyByte = Base64.decode(sessionKey);
	    // 偏移量
	    byte[] ivByte = Base64.decode(iv);
		try {
	        // 如果密钥不足16位，那么就补足.  这个if 中的内容很重要
	        int base = 16;
	        if (keyByte.length % base != 0) {
	            int groups = keyByte.length / base + (keyByte.length % base != 0 ? 1 : 0);
	            byte[] temp = new byte[groups * base];
	            Arrays.fill(temp, (byte) 0);
	            System.arraycopy(keyByte, 0, temp, 0, keyByte.length);
	            keyByte = temp;
	        }
	        // 初始化
	        Security.addProvider(new BouncyCastleProvider());
	        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding","BC");
	        SecretKeySpec spec = new SecretKeySpec(keyByte, "AES");
	        AlgorithmParameters parameters = AlgorithmParameters.getInstance("AES");
	        parameters.init(new IvParameterSpec(ivByte));
	        cipher.init( Cipher.DECRYPT_MODE, spec, parameters);// 初始化
	        byte[] resultByte = cipher.doFinal(dataByte);
	        if (null != resultByte && resultByte.length > 0) {
	            String result = new String(resultByte, "UTF-8");
	            return JSON.parseObject(result);
	        }
	    } catch (NoSuchAlgorithmException e) {
	        e.printStackTrace();
	    } catch (NoSuchPaddingException e) {
	    	 e.printStackTrace();
	    } catch (InvalidParameterSpecException e) {
	    	 e.printStackTrace();
	    } catch (IllegalBlockSizeException e) {
	    	 e.printStackTrace();
	    } catch (BadPaddingException e) {
	    	 e.printStackTrace();
	    } catch (UnsupportedEncodingException e) {
	    	 e.printStackTrace();
	    } catch (InvalidKeyException e) {
	    	 e.printStackTrace();
	    } catch (InvalidAlgorithmParameterException e) {
	    	 e.printStackTrace();
	    } catch (NoSuchProviderException e) {
	    	 e.printStackTrace();
	    }
	    return null;
	}


}
